With the new program, cardmembers save by synching their American
Express cards to their Twitter accounts. By tweeting hashtags
tailored to the store, customers load offers on to their card
that are then activated when they make a purchase.

Participating companies include big retail and food chains
like McDonald's, Whole Foods, Best Buy and H&M.

Like RetailMeNot's coupon app, this is another
deals program debuting at SXSW, though it differs by letting customers
interact directly with their own accounts to reap the savings.

And instead of saving beforehand, customers receive credits a few
days after their purchase.

Check @AmericanExpress for more deals tweets, then
watch the video below to see how it all works: